McIntosh C2500 Owners Manual

McIntosh Laboratory, Inc. 2 Chambers Street Binghamton, New York 13903-2699 Phone: [phone] www.mcintoshlabs.com

C2500

Tube Preamplifier

Owner’s Manual

The lightning flash with arrowhead, within an equilateral triangle, is intended to alert the user to the presence of uninsulated “dangerous voltage” within the product’s enclosure that may be of sufficient magnitude to constitute a risk of electric shock to persons.

WARNING - TO REDUCE RISK OF FIRE OR ELECTRICAL SHOCK, DO NOT EXPOSE THIS EQUIPMENT TO RAIN OR MOISTURE.

IMPORTANT SAFETY INSTRUCTIONS!

PLEASE READ THEM BEFORE OPERATING THIS EQUIPMENT.

1.Read these instructions.

2.Keep these instructions.

3.Heed all warnings.

4.Follow all instructions.

5.Do not use this apparatus near water.

6.Clean only with a dry cloth.

7.Do not block any ventilation openings. Install in accordance with the manufacturer’s instructions.

8.Do not install near any heat sources such as radiators, heat registers, stoves, or other apparatus (including amplifiers) that produce heat.

9.Do not defeat the safety purpose of the polarized or grounding-type plug. A polarized plug has two blades with one wider than the other. A grounding type plug has two blades and a

NO USER-SERVICEABLE PARTS INSIDE. REFER SERVICING TO QUALIFIED PERSONNEL.

third grounding prong. The wide blade or the third prong are provided for your safety. If the provided plug does not fit into your outlet, consult an electrician for replacement of the obsolete outlet.

10.Protect the power cord from being walked on or pinched particularly at plugs, convenience receptacles, and the point where they exit from the apparatus.

11.Only use attachments/accessories specified by the manufacturer.

12.Use only with the cart, stand, tripod, bracket, or table specified by the manu-

facturer, or sold with the apparatus. When a cart is used, use caution when moving the cart/ apparatus combination to avoid injury from tip-over.

13.Unplug this apparatus during lightning storms or when unused for long periods of time.

14.Refer all servicing to qualified service personnel. Servicing is required when the apparatus has been damaged in any way, such as power-

The exclamation point within an equilateral triangle is intended to alert the user to the presence of important operating and maintenance (servicing) instructions in the literature accompanying the appliance.

To prevent the risk of electric shock, do not remove cover or back. No user-serviceable parts inside.

supply cord or plug is damaged, liquid has been spilled or objects have fallen into the apparatus, the apparatus has been exposed to rain or moisture, does not operate normally, or has been dropped.

15.Do not expose this equipment to dripping or splashing and ensure that no objects filled with liquids, such as vases, are placed on the equipment.

16.To completely disconnect this equipment from the a.c. mains, disconnect the power supply cord plug from the a.c. receptacle.

17.The mains plug of the power supply cord shall remain readily operable.

18.Do not expose batteries to excessive heat such as sunshine, fire or the like.

19.Connect mains power supply cord only to a mains socket outlet with a protective earthing connection.

2

Thank You

Your decision to own this McIntosh C2500 Tube Preamplifier ranks you at the very top among discriminating music listeners. You now have the best. The McIntosh dedication to precision performance assures many years of musical enjoyment.

Please take a short time to read the information in this manual. We want you to be as familiar as possible with all the features and functions of your new McIntosh.

Please Take A Moment

The serial number, purchase date and McIntosh Dealer name are important to you for possible insurance claim or future service. The spaces below have been provided for you to record that information:

Serial Number:________________________________

Purchase Date:_ _______________________________

Dealer Name:_ ________________________________

Technical Assistance

If at any time you have questions about your McIntosh product, contact your McIntosh Dealer who is familiar with your McIntosh equipment and any other brands that may be part of your system. If you or your Dealer wish additional help concerning a suspected problem, you can receive technical assistance for all McIntosh products at:

McIntosh Laboratory, Inc.

2 Chambers Street

Binghamton, New York 13903

Phone: [phone]

Fax: [phone]

Customer Service

If it is determined that your McIntosh product is in need of repair, you can return it to your Dealer. You can also return it to the McIntosh Laboratory Service Department. For assistance on factory repair return procedure, contact the McIntosh Service Department at:

McIntosh Laboratory, Inc.
2 Chambers Street
Binghamton, New York 13903
Phone: [phone]
Fax: [phone]
Table of Contents
Safety Instructions......................................................		2
Thank You and Please Take a Moment......................		3
Technical Assistance and Customer Service..............		3
Table of Contents........................................................		3
General Information...................................................		4
Connector and Cable Information..............................		4
Introduction................................................................		5
Performance Features.................................................		5
Dimensions.................................................................		6
Installation..................................................................		7
Connections:
Rear Panel Connections...............................................		8
(Separate Sheet)...................................................		Mc2B
Connecting Components.............................................		9
Connection Diagrams
(Separate Sheets)...................	Mc1A, Mc1B and Mc2A
Remote Control:
Remote Control Push-buttons...................................		10
How to use the Remote Control.................................		11

Copyright 2013 © by McIntosh Laboratory, Inc.

Front Panel:
Front Panel Displays, Controls, Push-buttons
and Jack.....................................................................	12
Setup:
How to Operate the Setup Mode...............................	13
Default Settings.........................................................	13
Firmware Version......................................................	14
Reassign Source Inputs.............................................	14
Source Input Renaming.............................................	15
Input Level Adjustment.............................................	16
Power Mode...............................................................	16
Display Brightness.....................................................	17
Tube Lights................................................................	17
Passthru.....................................................................	17
Power Control Triggers 1 and 2.................................	18
Comm Port Baud Rate...............................................	19
Remote Control Codes..............................................	19
Operation:
How to Operate the C2500...................................	20-26
Trim Functions.....................................................	20-24
Processor Loop..........................................................	24
Tone Bypass...............................................................	24
Output Meters............................................................	25
Passthru.....................................................................	25
Optical and Coaxial Digital Inputs............................	25
USB Input Operation with a Computer.....................	25
Reset of Microprocessors..........................................	26
Resetting the C2500 to default settings.....................	26
Additional Information:
Photos...................................................................	27-28
Specifications.......................................................	29-30
Packing Instruction...................................................	31

3

Data

Signal

Main, Output 1&2,

Trig 1&2

and Pass-Thru

Power

Control

Meter Illumination

Control Ground

General Information and Connector Information

General Information

1.The C2500 uses Vacuum Tubes for amplifying the audio signal. The C2500 is designed to have only qualified Service Personnel perform any part(s) replacement including all the vacuum tubes.

2.For additional connection information, refer to the owner’s manual(s) for any component(s) connected to the C2500 Tube Preamplifier.

3.The Main AC Power going to the C2500 and any other McIntosh Component(s) should not be applied until all the system components are connected together. Failure to do so could result in malfunctioning of some or all of the system’s normal operations. When the C2500 and other McIntosh Components are in their Standby Power Off Mode, the Microprocessor’s Circuitry inside each component is active and communication is occurring between them.

4.The C2500 includes an Auto Off Power Save Feature and the default setting is enabled. For

additional information including how to disable it, refer to page 16.

5.Balanced and Unbalanced Inputs and Outputs can be mixed. For example, you may connect signal sources to Unbalanced Inputs and send signals from the Balanced Outputs. You can also use Balanced and Unbalanced Outputs simultaneously, connected to different Power Amplifiers.

6.The IR Input, with a 1/8 inch mini phone jack, is configured for non-McIntosh IR sensors such as a Xantech Model HL85BK Kit. Use a Connection Block such as a Xantech Model ZC21 when two or more IR sensors need to be connected to the C2500. When an external sensor is connected to the C2500 the Front Panel sensor is disabled to avoid possible interaction.

7.The C2500 internal Digital to Analog Converter Circuitry is designed to decode 2-channel PCM

(Pulse Code Modulation) Digital Signal present at the Coaxial and Optical Digital Audio Inputs. Other Digital Audio Signal Format Types will cause the Audio Outputs of the C2500 to be muted and the Front Panel Information Display will indicate an error message.

8.The Remote Control Supplied with the C2500 Preamplifier is capable of operating other components. For additional information go to www. mcintoshlabs.com.

9.When discarding the unit, comply with local rules or regulations. Batteries should never be

thrown away or incinerated but disposed of in accordance with the local regulations concerning battery disposal.

10.For additional information on the C2500

and other McIntosh Products please visit the McIntosh Web Site at www.mcintoshlabs.com.

Connector and Cable Information

XLR Connectors

Below is the Pin configuration for the XLR Balanced Input and Output Connectors on the C2500. Refer to the diagrams for connections:

PIN 1: Shield/Ground
PIN 2: + Output
PIN 3: - Output
PIN 2 PIN 1	PIN 1	PIN 2
PIN 3		PIN 3

Power Control and Trigger Connectors

The C2500 Power Control Out, Trigger and Pass-Thru Output Jacks send Power On/Off Signals (+12 volt/0

volt) when connected to other

McIntosh Components. An additional connection is for

controlling the illumination of the Power Output Meters on McIntosh Power Amplifiers. A 3.5mm stereo mini

phone plug is used for connection to the Power Control,

Trigger and Pass-Thru Outputs on the C2500.

Data Port Connectors

The C2500 Data Out Ports send Remote Control Signals to Source Components. A 3.5mm stereo mini phone plug is

used for connection.

N/C

Data Ground

RS232 DB9 Connector Pin Layout

1. N/C		6. N/C
2. Data Out (TXD)		7. N/C
3.	Data In (RXD)	8. N/C
4. N/C		9. N/C
5.	Gnd.

4

Introduction and Performance Features

Introduction

The McIntosh C2500 Tube Preamplifier is one of the finest Preamplifiers ever created with connections for both analog and digital sources. The C2500 Outputs have the ability to drive multiple Power Amplifiers. The C2500 reproduction is sonically transparent and absolutely accurate. The McIntosh Sound is “The Sound of the Music Itself.”

Performance Features

• Electromagnetic Input Switching with Level Trim

Adjustment

Digital Logic integrated circuits drive Electromagnetic Switches on all Inputs and operating functions for reliable, noiseless, distortion free switching. All eight Inputs on the C2500 can be matched in level, so there are no abrupt changes in volume levels between the different Inputs.

•Moving Coil and Moving Magnet Phono Inputs

The C2500 contains two different precision Phono Preamplifier Circuits. One for low output Moving Coil Phono Cartridges with selectable resistance loading, the other is for Moving Magnet Cartridges with selectable capacitive loading. Both circuits use the latest designs to provide the lowest possible noise and distortion. The RIAA Correction Equalization Circuitry utilizes close tolerance resistors and capacitors for an extremely flat frequency response.

•Digital Audio Inputs

The C2500 has Coaxial, Optical and USB Digital Inputs to Decode PCM Signals from an external source. The C2500 Up Samples the Digital Signal to 192kHz with 32Bit resolution before the Digital to Analog process begins.

• Balanced Inputs

The Balanced Inputs allow the connection of a source component using long cable lengths without a loss in sound quality.

• Precision Tracking Volume Control

Volume levels are controlled by a new Multi-Stage Precision Digitally Controlled Attenuator System with superb tracking accuracy.

•Variable Rate Volume and Balance Controls

The C2500 Tube Preamplifier’s Volume and Balance Control Circuitry provides an ideal rate of change with control rotation.

•Electronic Tone Controls with Bypass

Electronic Bass and Treble Circuitry allow volume level adjustments for low and high frequencies in precise one Decibel Steps. The C2500 remembers the Tone Control Circuitry Bypass Option for each input.

• Alphanumeric Fluorescent Display

The Front Panel Information Display indicates the Source Selection, Volume/Balance Levels and Setup Mode Selections. The display intensity is adjustable.

• Processor Loop

A Processor Loop is provided for connection of an external analog signal processor. The Processor Loop can be switched in or out of the signal path of any assigned Input.

• Pass-Thru Mode

The Automatic Pass-Thru Mode allows the C2500 to become part of a Multichannel Sound System for DVD-Audio, SACD and Home Theater Movies.

•Remote Control with External Sensor Input

The Remote Control provides control of the C2500 operating functions and McIntosh Source Components connected to it. Enjoy your McIntosh System from another room in your home by connecting an external sensor.

•Power Control Output and Trigger Assignment

A Power Control connection for convenient Turn-On of McIntosh Power Amplifiers, Source Components and Accessories is included. The Power Control Trigger Ouputs may be assigned to activate when a given Input is selected.

•Special Power Supply

Fully regulated Power Supplies and a special R-Core Power Transformer ensure stable noise free operation even though the power line varies.

•Fiber Optic Solid State Front Panel Illumination

The even Illumination of the Front Panel is accomplished by the combination of custom designed Fiber Optic Light Diffusers and extra long life Light Emitting Diodes (LEDs).

•Glass Front Panel and Super Mirror Chassis

Finish

The famous McIntosh Illuminated Glass Front Panel and the Stainless Steel Chassis with Super Mirror Finish ensures the pristine beauty of the C2500 will be retained for many years.

5

Dimensions

Dimensions

The following dimensions can assist in determining the best location for your C2500. There is additional information on the next page pertaining to installing the C2500 into cabinets.

Front View of the C2500

17-1/2"

44.5cm

7-

1/8"

7-5/8"

Side View of the C2500

18.1cm

19.4cm

16-1/2"

41.9cm

14-1/2"

36.8cm

Rear View of the C2500

17-1/8"

43.5cm

13/16"

10-9/16"

2.1cm

26.8cm

6-3/8"

16.2cm

1-15/16"

4.9cm

13 -1/4"

33.7cm

3/16" 6-9/16" 0.5cm 16.7cm

2"

5.1cm

6

Installation

Installation

The C2500 can be placed upright on a table or shelf, standing on its four feet. It also can be custom installed in a piece of furniture or cabinet of your choice. The four feet may be removed from the bottom of the C2500 when it is custom installed as outlined below. The four feet together with the mounting screws should be retained for possible future use if the C2500 is removed from the custom installation and used free standing. The required panel cutout, ventilation cutout and unit dimensions are shown.

Always provide adequate ventilation for your C2500. Cool operation ensures the longest possible operating life for any electronic instrument. Do not install the C2500 directly above a heat generating component such as a high powered amplifier. If all the components are installed in a single cabinet, a quiet running ventilation fan can be a definite asset in maintaining all the system components at the coolest possible operating temperature.

A custom cabinet installation should provide the following minimum spacing dimensions for cool operation.

Allow at least 6 inches (15.2cm) above the top, 2 inches (5.1cm) below the bottom and 1 inch (2.5cm) on each side of the Preamplifier, so that airflow is not obstructed. Allow 20 inches (50.8cm) depth behind the front panel. Allow 1-7/16 inch (3.7cm) in front of the mounting panel for knob clearance. Be sure to cut out a ventilation hole in the mounting shelf according to the dimensions in the drawing.

17-3/16"

43.66cm

	C2500 Front Panel			6-5/8"
	Custom Cabinet Cutout			16.84cm
		6"
	Cabinet	15.2cm
			Cutout Opening for Custom Mounting
	Front
	Panel
	Opening
	for Ventilation
	C2500 Side View
	in Custom Cabinet
		Cutout Opening for Ventilation
	Support	2-1/4"		Chassis
	Shelf			Spacers
		5.72cm
		9-1/8"
	C2500 Bottom View	23.18cm
			15"	15"
	in Custom Cabinet	Cutout
			38.10cm	38.10cm
		Opening
		for
		Ventilation
	1-1/16"	12-5/16"
	Note: Center the cutout Horizontally 2.70cm	31.27cm

on the unit. For purposes of clarity, the above illustration is not drawn to scale.

7

Rear Panel Connections

Rear Panel Connections

The identification of Rear Panel Connections for the C2500 Tube Preamplifier is located on a separate folded sheet contained in the Owner’s Manual Packet. Refer to separate sheet “Mc2B” for the Rear Panel Connections.

C2500 Tube Preamplifer Rear Panel

8

Connecting Components

Connecting Components

The C2500 has the ability to automatically switch power On/Off to Source Components via the Power Control connections. The Data Port Connections allow for the remote operation of basic functions using the C2500 Remote Control. With an external sensor connected to the C2500, remote control operation of the system is possible from another room and/or when the C2500 is located in a cabinet with the doors closed.

The connection instructions below, together with the C2500 Input/Output/Control Connection Diagrams located on the separate folded sheets “Mc1A/1B and Mc2A”, are an example of a typical audio system. Your system may vary from this, however the actual components would be connected in a similar manner. For additional information refer to “Connector and Cable Information” on page 4.

Note: Source components may be connected to the C2500 Balanced Inputs or Digital Inputs instead of Unbalanced Inputs. Refer to Setup “Reassigning Inputs” to activate them on page 14.

Power Control Connections:

1.Connect a Control Cable from the C2500 POWER CONTROL MAIN Jack to the Power Control In on the Turntable.

2.Connect a Control Cable from the Turntable Power Control Out Jack to the SACD/CD Player Power Control In Jack.

3.Connect a Control Cable from the SACD/CD Player Power Control Out Jack to the Tuner Power Control In Jack.

4.Connect a Control Cable from the C2500 POWER CONTROL OUTPUT 1 Jack to the Power Amplifier Power Control In Jack.

Note: If two Power Amplifiers are used, connect the Power Control Output of the first Amplifier to the Power Control Input on the second Amplifier.

5.Optionally connect a Control Cable from the C2500 POWER CONTROL OUTPUT 2 Jack to the Power Amplifier (Secondary Room) Power

Control In Jack.

6.Connect any additional Components in a similar

manner, as outlined in steps 1 thru 4.

Data Control Connections:

7.Connect a Control Cable from the C2500 TUNER DATA PORTS Jack to the TUNER Data In Jack.

8.Connect a Control Cable from the C2500 CD DATA PORT Jack to the SACD/CD Player Data In Jack.

9.Connect any additional McIntosh Components in a similar manner, as outlined in steps 7 thru 8.

Sensor Connection:

10.Connect a Control Cable from the C2500 IR Input Connector to the external Sensor.

Audio Connections:

11.Connect an Audio Cable from the C2500 TUNER

INPUT Jacks to the Tuner (Fixed) Output Jacks.

12.Connect an Audio Cable from the C2500 CD IN-

PUT Jacks to the SACD/CD Player (Fixed) Output

Jacks.

13.Connect the Audio Cables coming from the Turntable to the C2500 MC PHONO INPUT Jacks.

Note: If the Turntable has a Moving Magnet Cartridge connect the audio cables to the C2500 MM PHONO INPUT instead of the MC Input.

14.Connect Balanced Cables from the C2500 BALanced OUTPUT 1 connectors to the Power Amplifiers Balanced (Left and Right) Inputs.

15.Optionally Connect an Audio Cable from the C2500 BALanced OUTPUT 2 connectors to the

Power Amplifier (Secondary) Inputs.

16.Connect any additional McIntosh Components in a similar manner, as outlined in steps 11 thru 14.

Optional “PassThru” Connections:

17.Connect Balanced Cables from the A/V Control Center Front Left and Right Channel Balanced Output connectors to the BALanced 2 Input connectors.

Note: Refer to Setup “PassThru” on page 17 to activate the BALanced 2 Input.

18.Connect a Control Cable from the C2500 PASSTHRU to A/V Control Center Zone ZA Power Control Output.

Optional USB Connection:

19. Connect a USB cable with (type A to type B) connectors from the C2500 USB D/A Input to an available USB connector.

Ground Connections:

20.Connect the Ground Cable coming from the Turntable to the C2500 GND Binding Post.

AC Power Cords Connections:

21.Connect the C2500 and any remaining components’ AC Power Cords to a live AC outlet as illustrated.

9

Remote Control Push-Buttons

LED illuminates during the time a remote command is sent to the C2500

Switches the Trigger 1 and/or 2

Power Control Jack(s) On/Off, refer to “Setup, Power Control TRIG 1 and TRIG 2” on page 18 for additional information

Selects a Disc Player, Music Server or Recorder Function. Seek Stations Up or Down the AM/FM Dial. Select AM/FM Station Presets and performs various functions on a variety of McIntosh Components

Displays On Screen Functions on the McIntosh Music Server and a variety of other McIntosh Components

Adjusts the volume level up or down

Press to Power the C2500 ON

Press to Power the C2500 OFF

Press to change broadcast bands on an external McIntosh Tuner connected. Select certain functions on a variety of McIntosh Components

Selects On Screen Functions on a variety of McIntosh Components

Press TRIM and then the LEVEL Push-buttons to select and adjust various functions

Activates the TRIM

Stereo/Mono Mode

Mutes the audio

Selects AM Tuner Operating Functions and Disc Selection on certain McIntosh Disc Players

Selects Functions as a “shift” key when used with the AM or FM push-buttons to select Output 1 or 2

Scrolls through the available C2500 Inputs

Selects FM Tuner Operating Functions and Track Selection on certain McIntosh CD Players

Use to select tuner presets, disc tracks or any numbered operation

Scrolls through the available C2500 Inputs

Selects one of the eight available Audio Sources

Note: Push-buttons whose function is not identified above are for use with other McIntosh Products.

10